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Two complementary methodologies for extracting useful insights into electronic structure and bonding from contemporary wavefunctions are compared. The first of these, known as the analysis of domain-averaged Fermi holes (DAFH), mostly provides visually appealing descriptions of the role and the extent of electron sharing in chemical bonding. The second one, known as the fragment, atom, localized, delocalized and interatomic (FALDI) charge density decomposition scheme, uses the partitioning of certain localization and delocalization indices to focus on highly visual contributions associated with individual domains and with pairs of domains, respectively. Four variants of a FALDI-like approach are investigated here in some detail, mostly to establish which of them are the most reliable and the most informative. In addition to 'full' calculations that use the correlated pair density, the consequences for the DAFH and FALDI-like procedures of using instead a popular one-electron approximation are explored. Additionally, the geometry dependence of the degree of acceptability of the errors that this introduces for delocalization indices is assessed for different formal bond multiplicities. The familiar molecular test systems employed for these various linked investigations are the breaking of the bonds in H2 and in N2, as well as the nature of the bonding in B2H6, as a simple example of multicenter bonding. One of the key outcomes of this study is a clear understanding of how DAFH analysis and a particular variant of FALDI-like analysis could be most profitably deployed to extract complementary insights into more complex and/or controversial bonding situations. [ABSTRACT FROM AUTHOR]

A letter to the editor discussing the use of CD20 antigen-specific chimeric T-cell receptors in cellular immunotherapy for B-cell malignancies is presented.

Osteosarcoma, one of the most frequent secondary malignancies after the treatment of young patients with cancer, has only very rarely been observed in association with hematopoietic stem cell transplantation (HSCT). We report four patients who were identified by searching the database of the Cooperative Osteosarcoma Study Group (COSS) for patients whose osteosarcoma arose following HSCT. Transplant indications had been acute lymphoblastic leukemia (3) and sickle cell disease (1), and the stem cell source was bone marrow in all cases (three allo-geneic, one syngeneic). All four had received chemotherapy with alkylators as part of their conditioning regimen and/or first line therapy. The conditioning regimen included total body irradiation in three patients. The osteosarcomas arose at the age (adolescence) and sites (around the knee) typical for the disease. All four patients received chemotherapy as part of multimodal osteosarcoma treatment, and all four are currently alive, three in continuous remission at 5 7/12, 2 11/12, and 0 6/12 years and one with relapsed osteosarcoma at 4 1/12 years. One of the osteosarcoma-free survivors suffered a third malignancy, myelodysplastic syndrome. Osteosarcoma should be included among the secondary malignancies that can arise following HSCT. Multi-modal therapy according to guidelines for de novo osteosarcoma can lead to long-term survival in selected patients.Bone Marrow Transplantation (2003) 31, 353-359. doi:10.1038/sj.bmt.1703864 [ABSTRACT FROM AUTHOR]

In January 1983, the German Society of Pediatric Oncology started a cooperative trial (MAKEI 83) for non-testicular germ-cell tumors. The pilot phase closed in December 1985. The treatment regimen was stratified according to histology, tumor site and tumor stage. In malignant non-seminomatous germ-cell tumors (mNSGCTs), chemotherapy consisted of four courses of 3 mg/m2 vinblastine, on days 1 and 2 and 15 mg/m2 bleomycin on days 1-3, given by continuous infusion, and 20 mg/m2 cisplatin on days 4-8 with mannitol diuresis. Courses were repeated every 3 weeks. In mNSGCT patients with ovarian FIGO stages III-IV or extragonadal primaries, second-look surgery was carried out, followed by four additional courses of chemotherapy with 100 mg/m2 VP-16 on days 1-3, 1.5 g/m2 ifosfamide on days 1-5 with mesna uroprotection and 20 mg/m2 cisplatin on days 1-5 with mannitol diuresis. In patients with sacrococcygeal germ-cell tumors, en bloc resection of the tumor, including the coccygeal bone, was mandatory. During the registration period, 57 patients with mNSGCTs were entered: 37 protocol patients and 20 follow-up patients. The event-free survival for protocol patients at 57 months was 78% +/- 6% and that for follow-up patients was 40% +/- 10% (Kaplan-Meier): the crude survival for both groups was 83% +/- 6% and 54% +/- 12%, respectively. After a review by a panel of pathologists, the histological diagnoses in 7% of all registered cases of germ-cell tumors were changed. The results of the present studies show that the histological subclassification of mNSGCTs, tumor site and tumor stage no longer had prognostic value. [ABSTRACT FROM AUTHOR]